The architecture of traditional operating systems relies on address-based memory protection. To achieve flexibility at a low cost operating system research has recently started to explore alternative protection mechanisms, such as type safety. This dissertation presents an operating system architecture that completely replaces address-based protection with type-based protection. Replacing such ...

In the ESA Columbus Project, including in particular the European Space Station, applications are written in Ada and are distributed; moreover, the long lifetime of the space elements requires flexibility in order to support smooth software evolution. CHORUS is a distributed operating system, developed and supported by Chorus systèmes, which provides a basis for supporting efficiently distribu...

T HE microkernel story is full of good ideas and blind alleys. The story began with enthusiasm about the promised dramatic increase in flexibility, safety, and modularity. But over the years, enthusiasm changed to disappointment, because the first-generation microkernels were inefficient and inflexible. • Today, we observe radically new approaches to the microkernel idea that seek to avoid the ...

T HE microkernel story is full of good ideas and blind alleys. The story began with enthusiasm about the promised dramatic increase in flexibility, safety, and modularity. But over the years, enthusiasm changed to disappointment, because the first-generation microkernels were inefficient and inflexible. • Today, we observe radically new approaches to the microkernel idea that seek to avoid the ...

This paper presents the object access control and distribution strategies for the Nó// (reads parallel node) project, which aims to develop a high performance, low cost, multicomputer and a concurrent programming environment for it (Corso, 1993). Sharing resources is the main goal of multiprogramming environments (Andrews, 1990). Therefore, operating system must provide control mechanisms to ma...

T HE microkernel story is full of good ideas and blind alleys. The story began with enthusiasm about the promised dramatic increase in flexibility, safety, and modularity. But over the years, enthusiasm changed to disappointment, because the first-generation microkernels were inefficient and inflexible. • Today, we observe radically new approaches to the microkernel idea that seek to avoid the ...

Many of the performance improvements cited in recent operating systems research describe specific enhancements to normal operating system functionality that improve performance in a set of designated test cases. Global changes of this sort can improve performance for one application, at the cost of decreasing performance for others. We argue that this flurry of global kernel tweaking is an indi...